The Critically Poisoned Worker

Abstract

Exposures to toxicants in the workplace can cause severe illness and death similar to intentional poisonings and overdoses. In some cases, without a careful occupational history, the relationship between the job and the illness may be missed. Prolonged exposure to an insoluble gas, such as nitrogen dioxide after arc welding in a confined space, can cause a delayed pulmonary injury and acute respiratory distress syndrome (ARDS) that occurs one day later, when the link may go unnoticed. Careful questioning about the particular sequence of events is important when an illness occurs after performance of a common task. An example is exposure to phosgene gas after torch-cutting or welding metal that had been recently degreased with a chlorinated hydrocarbon solvent. Alternatively, a worker may experience a delayed illness such as metal fume fever (MFF) if he or she is welding on galvanized metal or had been working in close proximity to someone doing so. It is important to ask not only about the job of the ill worker but also about the nature of the workplace and the other processes being performed there.

Evidence obtained from well-designed cohort or case–control analytic studies, preferably from more than one center or research group.

II-3

Evidence obtained from multiple time series with or without the intervention. Dramatic results in uncontrolled experiments (such as the results of the introduction of penicillin treatment in the 1940s) could also be regarded as this type of evidence.

III

Opinions of respected authorities, based on clinical experience, descriptive studies and case reports, or reports of expert committees.